For refueling vehicles, a filling connection piece is usually provided whose opening for example, may be closed by means of a lockable turn-lock closure. The connection piece and closure for aesthetic reasons and in order to reduce the danger of injury are usually sunk into a refueling trough in the car body. The refueling trough is usually closable by means of a refueling flap and is thus hinged to the car body.
The design of the opening and closing mechanism varies with the known refueling flaps: the flap may be operated by hand and may be kept in the closed or open position by means of spring force. Another known refueling flap envisages a bar mechanism operable from the inner space of the vehicle by means of a pull wire, which lets the refueling flap flick open by means of a spring force as soon as the bar is actuated. This flap is then closed by hand so that the bar again clicks in and keeps the flap closed.
The opening and closing movement of these known refueling flaps is fast and abrupt when they are biased by a spring force, and also they act "rickety" when no spring is provided. By way of the fact that with the known spring guided embodiment form the flap flicks to the open or closed end position, corresponding abutment surfaces may wear. Furthermore irritating noises may be produced.